As shown in FIGS. 1 through 4b, a conventional spring contact 100 is an important element of an IC test socket, in which the spring contact functions to electrically connect a lead of the IC to a PCB.
Hereinbelow, the construction, operational function and problems of the conventional spring contact will be described in detail with reference to FIGS. 1 through 4b. 
The conventional spring contact 100 includes: an upper contact pin 110 which is provided with a contact portion 111 that has a predetermined shape and is brought into contact with a lead of a separate semiconductor IC to be inspected, two holding protrusions 112 and 113 that are provided in left and right sides of the spring contact and limit a length of an assembled spring and prevent the assembled spring from being displaced, a spring holding surface 150 that is formed by the two spring holding protrusions, and a body 118; a lower contact pin 130 that is coupled to the upper contact pin 110 in such a way that the two contact pins cross each other at right angles; and a spring 190 that is fitted over an assembly of the upper and lower contact pins at a position between the upper and lower contact pins. Here, the body 118 has two symmetric elastic portions 119 each of which has an oblique surface 122, a contact surface 123 and a locking protrusion 121 on an end thereof. A moving slit 120 is formed between the two elastic portions 119 and forms a moving space in which the lower contact pin can move; a stop surface 140 is formed on an end of the moving slit 120, so that the moving slit 120 movably receives the locking protrusions 121 of the lower contact pin 130. The body 118 further has a moving opening 116 and side walls 115, which make electric contact with the contact surfaces 123 and side contact portions 124 of the locking protrusions 121 of the lower contact pin 130. Here, one end of the moving opening 116 forms a stop bridge 117 and the other end extends to the spring holding surface 150 which is formed by the two left and right spring holding protrusions that function to limit the length of the assembled spring and to prevent the spring from being undesirably displaced.
Hereinbelow, the operational relationship of the spring contact will be described with reference to FIGS. 4a and 4b. 
FIG. 4a is a view illustrating the operation of the conventional spring contact, and FIG. 4b is a view illustrating the maximum compressed distance of the conventional spring contact.
Here, in FIG. 4a, the left-sided figure illustrates an initial assembled state of the conventional spring contact and the right-sided figure illustrates a state in which the spring contact has been compressed by a distance S.
Further, a distance Smax, by which the stop surfaces 140 of the upper and lower contact pins are moved from the initial assembled state that is shown in the left-sided figure of FIG. 4a to a state in which the stop surfaces 140 come into contact with each other as shown in FIG. 4b, is the maximum operating distance of the spring contact. In the above state, the stop surfaces of the upper and lower contact pins come into contact with each other, each of the contact surfaces 123 of the bodies of the upper and lower contact pins is placed in the moving opening 116 of an opposite contact pin, and each of the ends 149 of the bodies of the upper and lower contact pins reaches the holding protrusions 112 and 113 that are formed in an opposite contact pin so as to limit the length of the assembled spring and to prevent the spring from being displaced.